I think the correct answer from the choices listed above is option A. The statement that states a negative impact of chemistry on the society is that hazardous <span>coolants in refrigeration units were replaced. One example of this coolant is the </span><span>production and use of chlorofluorocarbons (CFCs) which replaced by more safer coolants.</span>
Answer:
Synthesis - 4
reversible- 2
exchange- 1
decomposition-3
Explanation:
In synthesis reaction two or more components combines to form a single product. example 2H2+O2⇒2H2O
In reversible reaction two reactants combine to form two products . The products then reacts and forms back the reactants. example N2 +3H2 ⇒2NH3
In exchange reaction there is an alternation of ions of reactants to form new products. AB+CD ⇒AC + BD
In decomposition reaction, molecules of a compound break down by the action of heat or light or catalyst. example CaCO3 ⇒CaO +CO2
Answer:
74,67 gr/mol
Explanation:
At STP 1 mole of an ideal gas has volume of 22,4 L. Since we know the volume of the gas we can find the number of moles of the gas. (300 mL=0,3 L)
n=0,3L/22,4 L=0,01339 mol
Since we know weight of the gas as 1 g, we can find the molecular weight as;
MW=1 g/0,01339 mol =74,67 gr/mol
The grey liquid is related to the white liquids because the change in colour is the result of a chemical change/reaction between the two white liquids.
Answer:
2.94 x
Explanation:
First we need to find out how many moles of ammonia there are, using the formula: Mass = mr x moles.
We know the mass is 83.1g, now we need to find the mR of ammonia - NH3.
N = 14, H = 1, so 14 + (3x1) = an mr of 17.
Moles = mass/ mr = 83.1/17 = 4.8882
Now we can multiply the moles by avogadro's constant to find the number of molecules:
4.8882 x (6.02 x
) = 2.94 x
molecules of ammonia